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> Is there a "how to.." for crank measurement, and bearing verification?
malcolm2
post Dec 16 2019, 11:07 PM
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I am gonna make a 2 liter from my 1.8. So I have a refreshed 71mm crank that I have been told has been ground to -0.010.

I measured as best as I can with a digital mic and got about 59.66 on the mains and 49.65 on the rod journals.

Where can I find the STD specs and ranges ? were they 60 and 50, respectively?

Since I know nothing about this crank, how can I verify the 71 mm measurement?
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Mark Henry
post Dec 21 2019, 03:24 PM
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Sounds like a lot. If you're right about #4 you'll be lucky to get it ground at .010 under.
You need to send it to a crank shop, once done they will tell you (tag) what sizes you need. I never use plastigage, nether does Raby IIRC. Your rods should at least have the big ends done.

Honestly if you're not doing that then it's a recipe for disaster.
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malcolm2
post Jan 20 2020, 08:59 AM
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QUOTE(Mark Henry @ Dec 21 2019, 03:24 PM) *

Your rods should at least have the big ends done.

Honestly if you're not doing that then it's a recipe for disaster.


OK, I am back on the engine.... at least research.

So what do you mean, "have the big ends done"?

I found rod bearings at CIP1.com that are listed only as STD or -0.010, etc... $33 for a set. I assume that the "under" listing is to note the machining on the crank. Is this what I should look for, simply -0.010?

If the rods were "done" would that mean that they have been trued up? Ground or polished or just re-bearing-ed?

Blizzard has provided me a set of 2.0 liter rods that he has balanced. So I have something to work with here. The link provided by superhawk above, only deals with 1.7 and 1.8 engines.... at least that I can find. 251 pages on the engine, so I could have missed it. So I am still looking to find the factory spec on the "big end" as a starting place and to determine if Mike's rods have been "done".

So question 1: how do you "DO" the rods?
question 2: What Rod bearings to get, how are they listed?

Thanks

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Posts in this topic
malcolm2   Is there a "how to.." for crank measurement   Dec 16 2019, 11:07 PM
Superhawk996   @malcolm2 My understanding is that this crank th...   Dec 17 2019, 06:17 AM
malcolm2   YES, It seems that @jtprettyman has passed it on...   Dec 17 2019, 08:46 AM
malcolm2   How about the 71mm measurement? Not that it matte...   Dec 17 2019, 08:51 AM
Superhawk996   How about the 71mm measurement? Not that it matt...   Dec 17 2019, 02:13 PM
Mark Henry   How about the 71mm measurement? Not that it mat...   Dec 17 2019, 11:26 PM
Mark Henry   I only use STD cranks or standard (under) cranks I...   Dec 17 2019, 09:24 AM
malcolm2   I only use STD cranks or standard (under) cranks ...   Dec 17 2019, 09:48 AM
Superhawk996   Also for what it’s worth, I provided this crank ...   Dec 17 2019, 02:34 PM
malcolm2   OK it passed the hammer test. very high pitched t...   Dec 17 2019, 06:30 PM
Superhawk996   With my method of measuring last night, I got a ...   Dec 18 2019, 08:53 AM
malcolm2   With my method of measuring last night, I got a...   Dec 18 2019, 10:03 AM
Superhawk996   Thanks for your input. I certainly hope you don...   Dec 18 2019, 02:58 PM
malcolm2   OK, maybe not the super duper accurate tools but I...   Dec 21 2019, 02:47 PM
Superhawk996   OK, maybe not the super duper accurate tools but ...   Dec 21 2019, 07:36 PM
Mark Henry   Sounds like a lot. If you're right about #4 yo...   Dec 21 2019, 03:24 PM
malcolm2   Your rods should at least have the big ends done....   Jan 20 2020, 08:59 AM
Superhawk996   So question 1: how do you "DO" the rod...   Jan 20 2020, 12:41 PM
malcolm2   Both micrometers were checked prior to the last me...   Dec 23 2019, 10:08 AM
Superhawk996   Both micrometers were checked prior to the last m...   Dec 23 2019, 10:34 AM
malcolm2   3) For hobbyists like myself, Plastigage can ser...   Dec 23 2019, 10:44 AM
malcolm2   UPDATE>>>>> Todd is the Director o...   Jan 14 2020, 08:38 PM
Superhawk996   Rod measurements align a whole lot closer to what ...   Jan 15 2020, 06:00 AM
jtprettyman   @Superhawk996 Yes, these were done with a very n...   Jan 15 2020, 08:58 AM
malcolm2   Rod Balancing, End-to-end. I also wondered how in...   Jan 21 2020, 08:30 AM


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